<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      body {
        margin: 0;
      }
      canvas {
        display: block;
        margin: 0 auto;
        background-color: #000;
      }
    </style>
  </head>
  <body>
    <canvas width="800" height="600" id="cvs"></canvas>
  </body>
  <script src="./ball.js"></script>
</html>
